USB hubs no big deal
Lots of Mac users (like me) over the years have accumulated assorted stuff like printers, scanners, joysticks, hard drives, etc. that don't have wireless capability, and add up one way or another to more than four. Apple has never produced a Mac with enough USB ports for some of us.
Amazon sells powered USB 3.0 hubs from four to seven ports ranging from $23 to $50, which should be enough as a single unit for most users. With the need to rip large CD libraries aggravated by Apple's silly itch for "thin" removing the ODD, that's one more port needed. Apple will make a few more billions from those of us lazy enough to just order their Superdrive along with the iMac and the Crucial RAM.
It's their usual arrogance deciding that no one needs an ODD in their AIO costing some of us another few bucks and another cable required until someone comes up with a Bluetooth CD ripper. There is some justification for outboard ODDs. I've had trouble with the built in ODD in my wife's mid 2010 iMac and my ancient PowerMac G5 tower, and it's a pain to have to carry the whole box to the shop.
Bite the bullet, buy a hub, and give up bitching at Apple. It's done. I've had two four port Belkin hubs for six years gathering dust in the cable nest on the floor behind my computer desk. When my 27" arrives next spring after the early buyer beta testers have done their thing, I'll replace my two old USB 2 hubs with a shiny new 7 port 3.0 hub for $49 or less as the market grows. They're backward compatible with USB 2 for old gadgets.